Year	Percent
2000-01-01	82.100
2001-01-01	82.750
2002-01-01	82.450
2003-01-01	81.075
2004-01-01	80.250
2005-01-01	79.925
2006-01-01	80.925
2007-01-01	82.250
2008-01-01	83.175
2009-01-01	82.375
2010-01-01	79.975
2011-01-01	79.375
2012-01-01	79.300
2013-01-01	78.175
2014-01-01	78.150
2015-01-01	79.000
2016-01-01	79.600
2017-01-01	80.400